Metal ski with cellular plastic structure



Sept. 28, 1965 ca. c. SULLIVAN ETAL 3,208,761 METAL SKI WITH CELLULAR PLAsTI STRUCTURE I Filed Sept. 4, 1963 United States Patent Office 3,208,761 Patented Sept. 28, 1965 V 3,208,761 METAL SKI WITH CELLULAR PLASTIC STRUCTURE George C. Sullivan and Robert S. Sullivan, both of 3085 Lake Hollywood Drive, Hollywood, Calif.

.FiledSept. 4,1963, Ser.N0.'306,459

7 Claims. (Cl. 280-1113) This invention relates to skis and has for its principal o'bjeets'to provide an improved .ski construction which shall have the advantages over skis hitherto manufactured andrused of being lighterin weight, simpler in construction}. inexpensive to manufacture, easy to assembly, and very efficient and durable in use.

The modern skis is usually made of a solid piece of wood orlaminated pieces of various woods, suchas ash, oak, birch-,spruce or hickory, or a combination thereof. Other'types of laminated skis have been proposed in which wood, metal and plastic laminae have been employed.

Skis, of this construction and type have certain dis- 1 advantages in that changes of temperature, moisture, and

rough usage cause warping or bending, and in some'cases breakage, usually due to the deterioration of the bonded laminations resulting from internal stresses caused by flexing and different coefficients of expansions, thus causing the ski to lose its resilienceand efiiciency. Otherski's have been proposed wherein a center core of wood, plastic, or other materials is preformed, and

then glued or laminated between an upper member and a lower runner of either wood, laminated plastic, or metal;

This arrangement, however, increases the weight of the ski and; in addition, causes'an abrupt change in the flexibility and, in some cases, a possible permanent set wherein the latter cannot be readily restored to its original shape.

An object of -the present invention is to provide a durable, resilient and efiicient ski which is inexpensive to manufacture due to its ease of assembly and requiring a minimum of machining and labor.

Another object of this invention is to provide a lightweight, 'two-piece aluminumor non-ferrous metal ski with preferably at least one piece made, of lightweight metal extrusion which is inexpensivein itself. Another object of this invention is the advantage of a lightweight metal extrusion, such as aluminum, or, an aluminum alloy, which maybe anodized for hardness and durability.

Still another object of the present invention is the use of foamed or cellular materials which, when applied as a liquid or semi-liquid and then allowed to react or foam has the ability to adhere to adjacent surfaces after curing,

2 I FIGURE is a cross-section taken. at line 5- 5 of larly to FIGURES 1-5, one ,will find an improved ski generally designated 10, having a top cover or member 11, and a lower portion or runner 12, generally U-shaped and preferably fabricated of aluminum or aluminum alloy extrusions, having sidewalls 14 and 15 which stand upwards from runner 12 and having grooves, substantially V'shaped in cross-section, 16'and 17, which-are cut or milledlongitudinally along the top inner face of side walls 14' and 15. The lower runner 12 is provided with a central guiding groove or channel 18 which feathers or diminishes as it progresses longitudinally to the front or upturned portion 19, becoming substantially flat at the front or upturned portion. Bottom portion of runner 12 is also provided with flanges 21 and 22 which extend outward from side walls 14 and 15 and diminish substantially at the waist 23 and flare outwardly as they progress longitudinally rearward from waist portion 23 and also forwardly to the upturned toe portion 19, as best shown in FIGURE 2. Side walls 14 and 15 are tapered gradually,

forwardly and rearwardly along the ski, by milling or machining, until they blend or feather in with the substantially fiat surface 24 of runner 12, as shown in FIGURE and having the characteristic of separate, individual cells which provide an effective seal against moisture and temperature and being completely metal enclosed.

Other objectives and features of the present invention will become apparent from the following detailed description of typical preferred embodiments throughout which reference will bemade to the accompanying drawings wherein: i e

FIGURE -1 is a side elevation of the preferred form 'of a ski; I

FIGURE 2 is a tion; v

FIGURE 3 is across-section taken at line 3-3 of FIGURE 2; Y

FIGURE 4 is a cross-section taken FIGURE 2; a

plan view of a ski embodying our invenat line 44 of l 1 and FIGURE 5.

Tapering the side walls 14 and-15 longitudinally permits lightening the ski and provides progressively greater flexibility as the end portions of the ski are approached. Obviously the U-shaped bottom member 12 and the upper member 11 could be reversed but such is not a preferred embodiment of the invention.

The upper portion or top cover 11 may be an extrusion or flat sheet stock provided with grooves 26 and 27 substantially V-shaped in cross-section, to mate in locking engagementwith grooves 16 and 17 when side walls 14 and 15 are sprung outwardly in assembly, as best shown by arrow A, and the top cover 11 is forced downwardly, as shown by arrow B, all as shown in FIGURE 6. Grooves 26 and 27 snap into engagement with grooves 16 and 17 of the side walls 14 and 15 effecting a relative simple and rigid structure of substantially rectangular crosssection. Top cover 11 can also be laced from one end to the other if springing is undesirable.

It is to be noted that the top cover 11 is provided with a diminishing waist, portion at 23 and flares progressively outward towards the toe and heel portions respectively; otherwise top cover 11 and bottom runner 12 are substantially the same in plan view, as best shown in FIG- The upper and lower portions, now locked into engagement by grooves 16 and 17 joining with grooves 26 and 27 of the top cover, are now shaped to desired form,

providing the upturned toe portion 19. These portions,

covering applied to the boti peara'nee.

foaming I r'esistant, that is,

{.tiall-y uniformly rectangular shaped groove provided at the-upper and inner surfaces of 3 I anodizing or hardening processes maybe used, a preferred and typical hardening process is described in U .S. Patent Nos. 2,692,851 and.2,692,852, issued October26, 1954.

It is also preferred to provide at least the bottom of the runner 12 with a dry lubricant material, such as 'molyb- I 'denum disulfide, graphite, or a-combination of the two materials with a suitable'resin, which can be applied and v curedfth'ereto, thus're'sulting in a-vsmooth, lubricated surfaee, 'withminimum frictional resistance.

In accordance with the present invention, a cellular 30. This eellularplastic3l can be a. foamed alkyd resin,

po1yisocyanate,; preferably it is installed into cavity bypo'ujrin-g into place through aperture 32 (FIGURE 4 and ,FIGURE 6) and then' allowed to react or foam up to form a relatively strong, lightweight core automatically adhering rigidly 'to the adjacent surfaces. 3 It is desirable to use a'cellular material such as described above, in thatit has a multiplicity of substantially uniformly shaped and proportioned spherical cells. These materials have .the desirable characteristic of adhering to the inner surfaces of runneri12, and 15, to effect a faces, once setting cover member 11 and side-walls 14 rigid bond or adhesion with said surand curing has been accomplished.

After the cellular plastic 31' has foamed and cured, with respect to aperture 32, itmay be cut off to'the level of the exterior top portion ll, thus providing side walls 14 and115 with a, protective coating and etfect a finished ap- Bleed holes 34 are providedin-top cover-l1 to facilitate the elimination of trapped air and gases created by the alkyd resinpolyisocyanate as it is poured into cavity 30 and expands therethrough. The bleedholes may then be plugged similar to"3'7,-shaved flush with top surface ofcover 11, as described above,.-or provided with a rivet to more securely fasten the sheets'together.

As best shown in FIGURE 7, a plastic covering 35 can be employed to coverv either the bottom runner 12- or top cover ll to provide a protective layer for said surfaces wh ch is attractive in appearance andfacilita'tes' ease of cleaning and waxing of. the ski. I f Theeharacteristics of a plastic employed'f or the abovedescribed purpose are that it must be tough-and weather it must maintain its physical characteristics within a. large frangeof temperatures normally encountered in the use of skis. It must be capable of' being bonded to metal and neither become. brittle at cold temperatures nor lose itsform at temperatures that wouldbe ;encountered in direct sunlight at high altitude. T

Referring toIFIGURE 8 of the drawingsya lower-run ner 12a is shown, having side walls 14a, and a substanorslot 36 is sidewalls 14a which join in locking engagement with cover 11a. If'de- "sirable, covering 35 of plastic or the like, is employed to provide a protective coating, as described above, and effects a smooth, continuous surface, joining with top portion'14' of sidewall 14a, thereby adding a finished quality and an adherent beauty to the ski.

, Having described only typical forms of the-invention,

we-do not wish to be limited to the specific details herein set forth but wish to reserve .to ourselves any variations or modifications that may appear to those skilled in the art and fall within the scope of the following claims:

10' plastic 3 '1 is applied to the substantially rectangular cavity We claim:

1. A lightweight metal ski comprising an upper member providing an upper surface, a lower member providing a lower surface, at least one of said members being a substantially U-shaped'section having spaced parallel side walls,-said sidewalls tapering in elevation forwardly and rearwardly from about the mid-section of said ski to form a substantially rectangular cavity. of decreasing cross-section, and means to join said upper and lower members consisting of an inner core. of cellular plastic material which is 'foar'nedin' situ, and adheres to the adjacent inner surfaces of'said members to provide a rigid bond therebetween to form a unitary structure.

2. A lightweight metal ski as set forth in claim 1, in which filler members extend between. said runner-edge and the top of said ski, secured to the outside of said side wall members. v

3. The invention-set forth in claim 1 in which the surfaces of said lower member subjected to wear are provided with an abrasion-resistant coating.

4. The invention setforth in claim 3 in which said abrasion-resistant coating is hard anodizing.

5. The invention set forth in claim 3 in which said abrasion-resistant coating is a plastic material.

6. A lightweight metal ski comprising an upper mem-' ber providing an upper surface, a lower member providing a lower surface, said lower member being a substan tially U-shaped section having spaced parallel side walls, said side walls tapering in elevation forwardly'and rearwardly from about the mid-section of said ski to form a substantially rectangular cavity of decreasing cross-seetion, and. means to bond said upper and lower members consisting of an. inner core of cellular plastic material which is foamedin .situ to adhere to the adjaeentinner surfaces of said members to provide a rigid bond therebetween and form a unitary structure, said lower surface extending beyond said side walls to form runner edges on said ski.

7. A lightweight metal ski comprising an upper cover member anda lower U-shaped member, said U-shaped member having sidewalls extending upwardly from a bottom surface, saidU-shaped member having portions of said bottom surface extending laterally outwardly from said side walls to form runner edges on said ski, said up per cover member having tongue portions and said side wall portions having grooves formed adjacent the top portions of said side walls to receive said tongue portions, said side wall portions tapering from maximum depth at the center of the ski to zero depth adjacent theends of the ski where the top and bottom portions meet, means to secure said topand bottom portions adjacent each end of the ski together, and a filler core means of plastic material foamed in situ to bond said upper and lower members into a unitary structure.

References Cited by the Examiner UNITED STATES PATENTS 9 It PHILIP ARNOLD, Primary 1?.l'llitil'iliff. A. HARRY uuvv; IiTrmnir/r'r. 

1. A LIGHWEIGHT METAL SKI COMPRISING AN UPPER MEMBER PROVIDING AN UPPER SURFACE, A LOWER MEMBER PROVIDING A LOWER SURFACE, AT LEAST ONE OF SAID MEMBERS BEING A SUBSTANTIALLY U-SHAPED SECTION HAVING SPACED PARALLEL SIDE WALLS, SAID SIDE WALLS TAPERING IN ELEVATION FORWARDLY AND REARWARDLY FROM ABOUT THE MID-SECTION OF SAID SKI TO FORM A SUBSTANTIALLY RECTANGULAR CAVITY OF DECREASING CROSS-SECTION, AND MEANS TO JOIN SAID UPPER AND LOWER MEMBERS CONSISTING OF AN INNER CORE OF CELLULAR PLASTIC MATERIAL WHICH IS FOAMED IN SITU, AND ADHERES TO THE ADJACENT INNER SURFACES OF SAID MEMBERS TO PROVIDE A RIGID BOND THEREBETWEEN TO FORM A UNITARY STRUCTURE. 